code_saturne User's Forum

Dear developers,

Please I want to ask a question about the inner iterations.

In GUI, in "Time settings"-"Velocity-Pressure algorithm", I can find two options available: "SIMPLEC" and "inner iterations", shown in the figure below. I'm confused about this. When I did LES simulations, I always chose SIMPLEC, does this mean I didn't have any inner iteration? This seems strange for an unsteady simulation. If I switch to "inner iteration" and set a number, then what will the velocity-pressure coupling method be?

Many thanks,
Ruonan

Hello,

The "inner iteration" here is different from the "sweeps" needed for non-orthogonal meshes, so you do not usually need them for LES. They are often used in fluid-structure interactions though, when the boundary condition is updated during the computation. I am not sure in which other cases they are needed..

So "inner iteration" is a bit different from SIMPLE.

Best regards,

Yvan

Hello Yvan,

Thanks for your reply! My understanding was wrong, I thought the inner iteration was used to decrease residuals when moving from this time step to the next time step. It seems I don't need to think about it for LES simulation.

Best regards,
Ruonan